Various development projects have examined ways of tracking working time in companies. The most familiar example is the clock card system which enable employees to clock in when they reach work, and to clock out when they leave. A timepiece of this kind, commonly known as the clock card unit, provides a clear documentary record that each employee has clocked up the correct number of contracted hours of work.
Self evidently, information obtained in this manner is confidential in nature. Employees only have access to information relating to their own arrival and departure times. At these times of day, no great analysis of information is really possible because several people are usually arriving or leaving at once, making it difficult for an employee to study at any length precisely how long he or she has spent at work.
There are also devices which make it possible to determine the time required to perform a specific task. A knowledge of these times makes it easier to raise invoices for work completed. One of these devices is described in document U.S. Pat. No. 3,719,037. This device features an hour and a minute hand and can record times extending up to a half-day of work. A pushbutton can be used to check arrival/departure times and intermediate breaks.
While a solution of this kind is well suited to the task of measuring working time spent on a specific task, it is not suitable for enabling employees to identify to any satisfactory extent the time they have actually been working for their employer.